The invention is concerned with a mechanism for feeding weft yarn stock bobbins to a loom and for carrying bobbin tubes of run-off stock bobbins away from the loom. A mechanism for feeding weft-yarn stock bobbins to a loom and for carrying away from the loom the bobbin tubes of stock bobbins which have been run off. The mechanism has a bobbin frame associated with the loom for at least two stock bobbins which may be fitted to bobbin holders with longitudinal axes. The bobbin holders may be aligned in relation to a common yarn guide member. A charging mechanism is movable towards the bobbin frame and away from it for exchanging for a fresh stock bobbin the bobbin tube of the stock bobbin which has been run off at the time. The mechanism also includes a delivery device for feeding to the common yarn guide member the piece at the start of the weft yarn wound on this stock bobbin.
The invention is further concerned with a method of operation of the mechanism.
In known mechanisms for feeding weft yarn stock bobbins to a loom from the EP-A 0 363 909 a number of stock bobbins is arranged on bobbin holders with their longitudinal axes aligned in a predetermined operating position with a common yarn guide member on the loom, associated with these bobbin holders. The bobbin holders are hinged to stationary carriers on a bobbin frame and each is pivotable between the operating position in question and a charging position intended for facilitating the exchange of the bobbin tube of the run-off stock bobbin for a fresh stock bobbin. In the case of the known mechanism, a delivery device is fitted to a pivotable arm on the charging mechanism. The delivery device has pneumatically actuated grippers for seizing the piece of weft yarn at the start of that wound onto the stock bobbin, by which the starting piece is seized and delivered to a positioning device which is arranged on the bobbin frame and by which the starting piece is fed to a suction tube of a delivery device for the weft yarn at the side of the loom.
The known mechanism demands a relatively elaborate control of the gripper and guide members for the stock bobbins which have to be mounted and the piece at the start of the weft yarn which has to be delivered. At every bobbin change the members have to be actuated and exactly positioned in the region of the bobbin frame.
The problem underlying the invention is to create a mechanism of the kind named initially, which enables simplification of the charging process and a shortening of the time it was hitherto necessary to spend on doing this.